Automatic roll feed for punch presses



Jan. 7, 1958 J. WlTTEK 2,319,072

AUTOMATIC ROLL FEED FOR PUNCH PRESSES Filed Sept. 23, 1955 6Sheets-Sheet 1 JGSEFH Mfr/5m v INVENTOR.

$ELLER$ a warm J. WITTEK AUTOMATIC ROLL FEED FOR PUNCH PRESSES FiledSept. 23, 1955 Jan. ,7, 1958 6 Sheets-Sheet 2 JOSEPH W/TTEK,

INVENTOR.

SELLERS 8 LATTA,

Jan. 7, 1958 wlT 2,819,072

AUTOMATIC ROLL FEED FOR PUNCH PRESSES Filed Sept. 25, 1955 6Sheets-Sheet 3 Jam 5 JOSEPH W/TTE/(o INVENTOR.

SELLERS 8 LATTA,

ATTORNEYS.

Jam. 7, 1958 J. WITTEK AUTOMATIC ROLL FEED FOR PUNCH PRESSES 6Sheets-Sheet 4 Filed Sept. 23, 1955 JOS'PH WIT rE/r,

- INVENTOR- SELLERS a LAT'TA,

ATTORNEY I.

Emma 9 1 J. WETTEM AUTOMATIC ROLL FEED FOR PUNCH PRESSES Filed Sept. 23,3,955 6 shee'ts sheet 6 JOSEPH M/T rag IN V EN TOR. James a: LA Tm ATTOE/VEYIS- 2'17 55 United Mem to V 2319,01: H 'AUroMA'Tic RCiLL FEEDFoR i uisicn l nnssns Josjih Witt'ek, Sherman Calif Wittek,

adniinis'tratbr of 'said Joseph Wittek, deceased Application septeniberi3, 1955, serial rimsazss This application is a continuation-impart ofmy pencling application Serial Number 425:693, filedjApril 26, 1954, nowabandoned, for Automatic Roll Feed for Punch Presses. Y I

The general object of the invention is ta provide an improved feedingdevice for the automatic feed of ribbon sheet material into a punchpress. I

A particular object is to provide in an autoniatic feeding device, anovel supporting deck mounted on four pillars, within the confines ofwhich the upper pressure applying feed rolls are carried. i p j v p HAnother object is to provide an improved automatic trip mechanism forarresting the feed in response to downward movement of the tamer a punchpress in which the feed mechahism is installed, and for, reestablishingthe feed as the r'ati'r ascends after having completed a punching orforming stroke. j

The invention is particularly directed to the provision of an improvedarrangement of release lever and release care, such that there will be aquick-releasing action in the initial stages of depression of theleverby the ram, followed by fairly wide range of furtherdownwardmovement of the lever which is accommodated Without. anysubstantial additional release movement, whereby various rain strokes ofvarying amplitudes ma be accommodated by the same feed controlmechanism. I j

A further object to provide such ah arrangement having relatively simplemeans for effecting ah indexing adjustment of the release lever inrelation to the release cam.

A further object is to provide impreve'd; straightening roll mechanismin connection with a roll feed apparatiis.

Another object is to provide an improved locking mechanism for lockingthe feed rolls in their released positioris,

Other objects will become apparent in the ensuing specifications andappended drawing in which:

Fig. 1 is a perspective view of the automatic feeding device mountedrelative to a punch press, the punch press parts being shownschematically;

Fig. 2 is. a side elevation of the feeding device from the rear sidethereof;

Fig. 3 is a sectional view taken on the line 3--3 of Fig. 4;

. Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2;

Fig. 5 is a fragmentary sectional view taken on the line 55 of Fig. 4; r

Fig. 6 is a fragmentary sectional view similar to Fig. 5 with the.locking mechanism in locking position;

Fig. ,7 is afragmentary detail view taken on the line 7-7 of Fig. 2;

Fig. 8 is an enlarged schematic view showing several positions of theroll lifting mechanism in the roll lifting operation;

Fig. 9 is a fragmentary d'etaihview of a modified construction of thestraightening rolh, N

.Fig. 1.0 is a sectional view taken on the line lib-10 of Fig. 9;

'ice

2 M Fig. 11 is asideview,partially broken away and .in section, of animproved modified form of the invention; .Fig. 'l2isa'pla'nview ofthesame; j p a Fig. 13 is a transverse sectional view taken on the line13 513 of Fig. 12

Fig. 14 is a detail sectional view showing the trip lever and releasecam mechanism; and g J Fig. 15 is a. detail showing the attachment ofthe trip lever to the cam shaft. j

The form of the invention shown in Figs. 1-10 Referring now to thedrawings in detailpl have in Figs l-ll'), onejform of thel invcntion aseinbo died in an automatic feeding device includin'g a h ase Ac rh;prising transversely extending the bars A and Af w ch anchor theupwardly prejec'ting and longitudinally extendin'g rails 1 and 2 inspaced parallel fashion relative to each other. The rails carry thefixed rolls 3 an d 4 (see Fig. '3), said lower rolls being rotatablyjournalled in the; opposed railmembers. An upper deck B carries theadjustable rolls 5 and 6 by means of the carriage, assembly C; Theplatform memberB is carried on fourupright posts 7, 8, 9 and 10, whichposts are carried on the rail members 1 and 2, The lower ions are drivenfrom shafts D through the gears B, such gearing alsoservin'g to drivetheupper rolls. The base A is-ada ptedto be mounted, for example, on thebolster plate F of the punch press F b'y means of bolts 1a projectingthrough the rails and through the filler plate 1b which extends betweenthe rails and is of the same thickness as tie bars A and A". In somecases the filler plate may not be needed and can be removed. The crankshaft of the punch press (not shown) has a sprocket mounted "on one endthereof (said sprocketnot being shown) for driving a chain G whichdrives the shaft D. The ram H of the punchpress has an arm-fastenedthereto for ac'tuating the roll-releasing mechanism J at a predeterminedmoment in the cycle of operation of the punch-press. A ribbon of stockKris fed between the guide rolls L, then through the straightening rollsM and thencet-hrough the feed rolls preparatory tobeing operatednponbythe upper die which is held in the ram of the punch press. The.crankshaft of the punch press transmits a positive diiVemtO- the gearingE.by means of the chain G and the. speed. of rotation of: thedrive shaftD may be' prer selected by any one of various speeds-by; selectivelyvarying .the ratio of thesprocket 13 and/or the sprocket (not. shown) onthe punchpress crankshaft. The idler sprocket .11 is. rotatably.journa-lled .on the shaft 14 which is anchored to the bar 15, which inturniis anchored to..the upper. surface of the platform B. The shaft 14may be integral with the bar 15 if desired. The second idler pulley 12is rotatably journalleduon the. cylindrical stud -16..which is anchoredbetween the clamp. bars 151 and-18- .by means ofthe .screws 19. Theopposite ends of the clamp bars .are. adjustably anchoredto the. shaft14 by means of the. screws 20. By loosening the screws 20 slightly, theclamp. bars may be swung aboutthe axis of the shaft 14for taking uptheslack in the drive chain; The .drive: shaft D is rotatablyjournalled' .at one. end in .the extension 21. andthe extension 22 ofthe base-A. These extensions are. preferably parallelto each.- other.The bevel gear 23 drives the bevel gear 24 and. the .bevel gear 25drives the bevelgeai 26.; The gears 23 and .25 are adjnstably fixedtothe drive shaft D by rn'eansofthe set screws 27. and 28. V The gears 24and 26 are compound gears having the bevel gear teeth at their. outerends andhaving the spungears 29 formed on their inner ends. The spurgears 29 drivethe spur gears .30. and 31-which are removably .anchored'10 the trunnionv portions 32 and 33 which are fixed to. the upperrollers- 5i. and: 6.- compound gears 24-49 and 26--29 are removablyfixed to the trunnion portions 34 and 35 which are anchored to the lowerrollers 3 and 4. The rollers have trunnions 36, 37, 38 and 39 at theends thereof opposite from the ends on which the gears are mounted. Thetrunnions 34 and 35 are rotatably journalled in sleeve bearings in therail 2 and the trunnions'38 and 39 are rotatably journalled inappropriate sleeve hearings in the rail 1. The lower rollers 3 and 4 arethus rotatably carried by the ,opposing rails 1 and 2 in fixed positionsof adjustment relative to the base A.

The trunnions 32 and 33 are rotatably journalled in the bearing block 40and the trunnions 36 and 37 are rotatably journalled in the bearingblock 41. these trunnions may be journalled in appropriate sleevebearings positioned in the bearing blocks, if desired. The bearing block40 is carried on leader pin 42 and the bearing block 41 is carried onthe leader pin 42. Each bearing block has a vertical bore 44 and 45therein and a counterbore 46 and 47 respectively. The lower ends ,of theleader pin 42 and 43 are received in the bores 44 and 45 respectivelyand the bolts 48 and 49 are internally threaded into the leader pins 42and 43 respectively to securely anchor the bearing blocks 40 and 41respectively to the leader pins. Cylindrical bearings 50 and 51 projectthrough the platform B into the counterbores 46 and 47 respectively ofthe bearing blocks and said sleeve bearings are anchored to the platformB as by means of spot welds v.52. A roller 53 has trunnion portions 54and 55 rotatably journalled in the upper ends of the leader pins 42 and43 respectively.

Each of the bearing blocks 40 and 41 have bores of substantial depth atthe opposite ends thereof into which the compression springs 56 arereceived. The under surface of the platform B is preferably providedwith four shallow bores for receiving the upper ends of the compressionsprings 56. The compression springs continuously urge the upper rollsand 6 toward the lower rolls Each of 3 and 4 and consequently applyconsiderable pressure to the surface of the ribbon of stock K whichpasses between the four rolls and is positively fed through such rollsby the frictional engagement of the rolls on the opposite surfaces ofthe stock. The lower ends 57 and 58 of the bearing sleeves and 51 arespaced sufiiciently far from the annular shoulders which are formed atthe bottoms of the counterbore 46 and 47 to permit the up and downmovement of the bearing blocks 4t) and 41 relative to sleeves 50 and 51in the operation of the pressure roll releasing mechanism I as will bemore fully explained hereinafter.

The platform'B and its supporting pillars 7, 8, 9 and 10, together withthe bearing guides 50 and 51 provide the necessary supporting structurefor the pressure applying rolls, the bolts 7a, 8a, 9a, and 10a beingthreaded into the rails 1 and 2 to anchor the platform B relative to thebase A.

A'pair of straightening rolls 60 and 61 are mounted on the rails 1 and 2and serve to substantially eliminate any kinks in the ribbon stock K asit is fed through the feeding rolls. The lower straightening roll 60serves to correct any downwardly directed kinks in the stock and theupper straightening roll 61 serves to correct any upwardly directedkinks in the stock so that all kinks in the stock are substantiallyironed out before the stock reaches the die of the punch press. Thelower straightening roll 60 has trunnions at either end rotatablyjournalled in the bearing blocks 62 and 63 which are journalled in andrest by gravity in appropriate bores in the rails 1 and 2 respectively.The upper straightening roll 61 has trunnions at either end journalledin the bearing blocks 64 and 65. Each of the bearing blocks 64 and 65are mounted in the rails 1 and 2 respectively in the manner as shown indetail in Fig. 3, wherein the bearing block 65 may have a cylindricalexternal surface which is journalled for reciprocable movement in avertical bore 66 in the rail 2, a compression spring abutting theannular shoulder formed at the base of the bore and continuously urgingthe bearing block upwardly to maintain the straightcning roll 61 in theelevated position above the stock K. A bolt 67 extends loosely through abore in the annular shoulder at the base of bore 66 and is threaded intothe end of the bearing block 65, the bolt head engaging the under faceof the annular shoulder to maintain the roll 61 in a fixed position ofelevation when upward pressure is exerted on such roll, as when sameencounters an upwardly directed kink in the stock. It will be understoodthat the bearing block 64 is mounted in rail 1 in a manner similar tothe mounting of bearing block in rail 2. i 1

A pair of guide rollers 68 and 69- are rotatably journalled about thevertical axes of the trunnions 70 (see Fig. 7), said trunnions beingformed on the upper ends of the slide blocks 71 which may be movedaxially along the supporting rod 72 by loosening the bolts 73. The guiderollers may thus be adjusted along the length of the rod 72 and thenspaced apart from each other a sufiicient distance to accommodate thewidth of the stock K, thereby to guide the stock in the properlongitudinal alignment through the feed rolls and prevent same fromshifting laterally relative to the feeding 'device. The stock at theopposite end of the feeding device is guided against lateral shifting bythe appropriate guiding devices on the punch press die. Each end of therod 72 is re.- ceived in bores in the bearing blocks 74 and 75respectively and the rod is removably anchored within the hearing blocksby means of the set screws 76. The bearing blocks have trunnion portionswhich are mounted in the ends of the rails 1 and 2 and anchored with setscrews 76a. The guide rollers 68 and 69 may be moved outwardly on rod 72beyond the inside corners at the ends of the rails 1 and 2 toaccommodate stock of maximum width.

The stock which is fed through the feed rolls at a predetermined speedthroughout a portion of the cycle of operation of the punch press, ismomentarily arrested while the ram H of the press performs the punchingoperation. The movement of the stock through the feed rolls must bequickly arrested just prior to the punching operation and to accomplishthis it is necessary to quickly release the tension which is exerted bythe upper rolls 5 and 6 against the stock through the medium of springs56. The operation of the mechanism for lifting the pressure rolls 5 and6 is synchronized with the stroke of the punch press and this rolllifting mechanism is carried on top of he platform B.

A lever 77 of considerable width is anchored to a fulcrum bar 78 whichhas trunnion portions at either end thereof rotatably journalled in thebearing posts 79 and 80. The inner end of the lever has a cam surface 81formed thereon which engages the cylindrical external surface of theroller 53. An arm 82 is removably fixed to the ram of the punch pressand has an adjustable striking rod 83 extending through the boss 84 atthe end of the arm. The rod may be adjusted axially of the boss byloosening and then retightening the nut 85, to accurately predeterminethe moment during the stroke of the ram when the lower end of the rod 33engages the handle end 86 of the lever 77. The fulcrum of the leverbeing the axis of the fulcrum bar '78, the greater portion of the weightof the lever is located on the side of the fulcrum of the handle portion86 and when the punch press ram is in its uppermost position, the weightof the handle portion 86 of the lever, by gravity, causes the oppositeend of the lever to always remain in contact with the undersurface ofthe roller 53 preparatory tothe pressure roll lifting operation. Whenthe lever is in its position of rest as shown in Figs. 1 and as shown insolid lines in the schematic view in Fig. 8, the corner 87 of the leveris in engagement with the lift roller 53, said corner 87 being the pointof commencement of the cam surface 81 at the free end of the lever. Whenthe striking rod 83 engages the outer end of the lever, the corner 87causes the lift roller 53 to be quickly lifted a pre-determined distancein proportion to the distance of travel of the lever about its fulcrum,then continued oscillation of the lever about the axis of the fulcrumbar 78 brings the cam surface 31 into engagement with the undersurfaceof the roller 53 and the rate. of lifting ofsaid roller is only nominalcompared to the initial lifting rate accomplished by the corner 87,since some additional lifting of the roller 53 is necessary to permitthe lifting lever to operate about its fulcrum throughout the remaininglength of the stroke of the punch; press ram after initial contact hasbeen made by the striking rod 83 with the lever, however, the totalamount of lift must be controlled so that the gears 29 remain in mesh atall times with gears 34) and 31. it will be noted in viewing Fig. 8 thata line drawn through the axes of the roller 53 and the fulcrum bar 78establishes a center line and the cam surface 81 at its pointof contactwith roller 53 re mains on the left side of this center line, viewingFig. 8, and never goes beyond dead center. in Fig. 8 I have shownschematically how the roller 53 is lifted a substan tial distance duringthe initial oscillatory movement of the lever and the subsequent amountof lifting of the roller 53 by the cam surface 811s very slight.

in some instances it may be desirable to lock the pressure rolls 5 and 6in lifted or released positions and this may be done by means of thelock arm 88 which is mounted on top of the bearing block 89 and which isfree to swing about the axis of the screw 90 which is threaded into theplatform B. The lock arm 88 may be swung about until the end 91 thereofextends beneath the lift roller 53. The wing nut 92 may then betightened and the subsequent releasing of the lever 77 causes the lockarm to hold the lift roller 53 in a position where the pressure rolls 5and 6 are lifted away from the stock K against the tension of thesprings 56. in the modified form of construction disclosed in "Figs. 9and it) the straightening roll. 61a is mounted for quick removal fromthe bearing posts 64 and 65 without affecting the pre-determinedadjustment of bolts 67a. Removable pins 9 1 are received in the bores 95in the opposite ends of the roller 61a, said roller being rotatablyjournailed on said pins. The pins 94 extend through the diametricalbores 96 in each of the aforementioned bearing posts and the thumb typeset screws 97 anchor said pins relative to the bearing posts. In orderto remove roller 61a it is only necessary to loosenthe thumb screws 97and then withdraw the pins 94 until the ends of said pins are completelyremoved from within the bores 95 in the roller. The pins do not need tobe completely removed from the bearing posts and it is desirable toleave them in the bearing posts to prevent their becoming lost.

The lower straightening roll 66a is preferably mounted so as to beadjustable in a vertical direction relative to the rails 1a and 2a,consequently, it is rotatably journalled at itsopposite ends in thebearing posts 98 which are slidably received in the vertical bores 99 inthe rails 1a and in. T he bolt 93 is threaded through the undersurfaceof the rails .la and 2a and the inner ends of said bolts abut the lowerends of the bearing posts 98, thereby supporting same. The roller 60amay be adjusted to any desired height relative to the rails bytightening or loosening the bolts 93 and then tightening the locknutsitltl against the undersurface of the rails in order to lock the bolts93 in the selected positions of adjustment. The entire roller assemblyincluding roller 60a and bearing posts 98 are positioned in holes 99 bygravity and may be removed by simply withdrawing same the adjustment ofscrew 93 remains unaffected.

The deck B is anchored at each of its four corners to the pillars 1111,each of which are slidably received in the ,vertical bores 102 in therails 1a and 2a (only one pillar and one rail bore being. shown in Fig.9). The

pillars 101 are preferably solid cylindrical pillars internally threadedbores at eachend int-o which; the bolts 103 and 1 04 are threaded, Itwill beunderstood that there are four sets of these bolts for use witheach ofthe four pillars. t

Referring to Figs, 1,, 2 and 3 I have provided-a friction brakemechanism comprising a lower bar, 106 and: ,an upper bar 107. The bolts108 are threaded. through the lower bar and oninto the rails land 2..Compression springs 109 urge the upper bar toward the lower bar, theupper her being reciprocable on the bolt shanks. The stock K is :guidedbetween the upper and; lower bar and the upper bar has tensionedfrictional contact with 'the stock which is not sufficient tointerferewith the movement of the stock through the feed rolls butwhichis sufficient to hold the stock in its arrested positionduring thepunching operation and while the pressure rolls are in released orlifted position out of contact with the stock.

The feeding device may be operated in either direction by reversing thedirection of rotation of the pressure and idler rolls, this beingaccomplished by removing shaft D and reversing the gears 23 and 25 onthe shaft in a known manner.

The preferred form of the invention, Figs. 11-1'5 Referring now to Figs.11-15 inclusive, 1 have shown therein an improvement upon the mechanismdescribed above. in Fig. 11, the apparatus is viewed substantially fromthe viewpoint of the punch press operator, and is disposed to the rightof the ram-dieaxis, the strip K feed ing from right to left, through asinglepair of feed rolls 3, 5' (instead of the dual painof rollspreviously described) and the release lever I projecting leftwardtointersect the pathof vertical reciprocation of the ramcarried actuatorfinger 83. t V v V Upper feed r0115 has its trunnions 33, 36 journalledin bushings in pillow blocks 40 and 41 which are suspended on the leaderpins 50, 51, the latter having re duced, threaded lower ends threadedinto pillow blocks 40, 41 as shown. Lower feed roll has its trunnions35, 38 similarly journalled in sill rails 1 and 2. Forward trunnions 3638 project forwardly of block 41 and rail 1 respectively and thereprovided with meshing gears 31, 29. Bevel gears 25, 26' transmit drivefrom sprocket chain driven drive mechanism G, 13, D as in thearrangement described above.

The release lever J is secured by bolts 116,. 116 to a hub 117 which isin the form of a split yoke clamp. adjustably secured to the cam shaft55 by means of which the roll carriage 41 is elevated, for releasing thedrive. An indexing adjustment of lever I relative to cam shaft 55 may beeffected by loosening clamp screws 116" of clamp hub 117, shiftingrelationship between lever and cams, and re-tightening screws 116.Formed integrally on shaft 55, at opposite ends of hub 117 (Fig. 14) area pair of cams 118 which bear against a fulcrum roller 119 in a mannersuch that, as finger 83 commences to depress the trip lever I, therewill be an initial stage of operation wherein shaft 55 is liftedrelatively rapidly for a relatively small increment of ram movement,thus to quickly release the grip of feed rollers 5, 3,. from the workstrip K; whereas, when the feed is thus completely released, the cams118 will continue to rotate against fulcrum roller 119 with only a veryslight additionallift of shaft 55 and roller 5. This is effected byproviding on each cam 113 a flat face 120 which rests against fulcrumroller 119 in tangential relation as shown in: full lines in Fig. 14, inthe normal, raised position of release lever J, and providing, beyondfiat 120, an arcuate bearing face 121 that is almost concentric with theaxis of shaft 55. Where flat 120' intersects arcuate face 121, there isan apex 122. Between a radius of shaft 55.normal to fiat 120' and up toapex 122, the flat 120 Pro vides a rapid rise in the cam. The risingmovement trans mitted to shaft 55 accelerates to a maximum rate as apex122 approaches the common radius between shaft 55 and fulcrum roller119, and it is in this stage that the rapid release of the drive iseffected. As apex 122 intersects this common radius, the rapid risesharply abates and substantially a dwell action ensues as arcuate face121 rides against fulcrum roller 119.

' An important-feature of the invention is the wide amplitude ofdownward movement of release lever I beyond the release point, providedby the extended circumference of arcuate cam face 121 with nearly zerorise. Sufiicient allowance for additional upward movement of feed rollerand leader pins 51 against the yielding resistance of coil springs 56,is provided so as to allow the lever J to stop at any point along itsextended stage of further movement beyond the release point. Thus themechanism adapts itself to a wide range of amplitudes of'ram strokebeyond the point where finger 83 initially engages lever J withoutaffecting the operation of the feed apparatus.

A further important feature of the invention is the provision forautomatic return of the lever I back to its normal, raised position,following the return upward movement of the ram and operator finger 83.This is provided for by a slight, constant rate rise in arcuate faces121 from apexes 122 up to the limit of lever depression,-which is morethan 60 degrees beyond the point of starting operation of the cams. Thisrise is established at a minimum to provide the substantially dwellaction referred to above, and yet is sufficient so that, as the pressureof springs 56 is exerted to move the shaft 55 downwardly as permitted bythe upward withdrawal of operator finger 83, the camming action ofarcuate face 121 against fulcrum roller 119 will be effective to liftthe lever I back to its starting position and allow the shaft 55 to thusreturn to its lowered position wherein feed roller 5 engages the work Kagainst feed roller 3. The angle of face 121 may be within the range of2 degrees to 5 degrees and is substantially uniform throughout itscircumferential extent so that adequate camrning action combined withminimum rise in this range, is attained.

Because of the automatic return action derived from the rise in camfaces 121 and the pressure of springs 56, the cams 118 will not lockagainst fulcrum roller 11% at any point in the full range of thepressure of lever I. The invention does however provide for locking thefeed roller 5 in its elevated, released position. Such locking mechanismcomprises a lip 1Z5 projecting beyond the rear end of hub member 117(Fig. 14) together with a locking lever 126', pivoted on a screw 127which is anchored in a bracket block 123, and a roller 129, carried bylever 126 in a position to engage beneath lip 125 with a camming action,as lever 126 is swung upwardly and over in the direction indicated bythe arrow in Fig. 13. The are of movement of roller 12) in thisoperation is such that the roller will engage the lip 125 at one sideand will pass transversely beneath the lip to a point adjacent the otherside, beyond dead center with reference to pivot 127, at which pointlever .126 will engage a stop pin 130 in bracket block 128, thus lockingthe lever 126 under the back pressure exerted by lip 125 as drawndownwardly by springs 56. In this locking position, lip 125 will beelevated to the position indicated in dotted lines in Fig. 13, and triplever I will be shifted downwardly well beyond the work release point,thus releasing roller 5 from the work.

Lever 126 may be provided on its outer end with a knob 131 for actuationof the lever.

Bracket block 128 is mounted solidly upon deck B, being secured theretoby screws 132. Being arranged at the opposite end of trip lever J fromthe end that is engaged by the actuator finger 85, it does not interferein any way with the normal operation of lever J by the punch press ram.At the same time, its operating range is disposed above the deck B andabove the rollfeed mechanism therebelow, where it can be easily andefficiently manipulated to effect the locking of the rolls in releasedposition whenever desired.

This modified form of the invention embodies an improved mechanism forspring loading the upper feed roll 5 downwardly against Work. Suchmechanism comprises the coil springs 56, caged in bores 57 in pillowblocks 41, their lower ends seated against the bottoms of bores 57 andtheir upper end projecting above pillow blocks 41 and piloted aroundabutment plugs 133. Each plug 133 has a flange 134 at its upper end,providing a shoulder against which the upper end of a respective spring56 is compressively engaged, and with a central socket in which isreceived the lower end of an adjustment screw lflo'that is threadedthrough the deck B as indicated in Fig. 11. Coil springs 56, two foreach pillow block 41, are disposed symmetrically on opposite sides ofthe axis of shaft 32 of upper roll 5. A singleset of rolls 5, 3,symmetrically arranged between the transverse planes of posts 8 and 10,is employed in this form of the invention.

The invention may utilize the upper roll 5 as one of the series M ofstraightening rolls including rolls 60 and 61. Rolls 6%) and 61 arearranged at respective heights such that the work strip K, in passingover roll 60, is bent downwardly. A very slight upward bend is given tothe work strip K as it passes between feed rolls 3, 5, by the operationof the brake 106, 107 between which the strip K passes after leaving thefeed rolls 3, 5. The brake leaf 106 may have its upper face on a levelwith the top of roll 3, but the top of roll 60 is somewhat higher thanthe top of roll 3 and consequently the strip assumes a slight downwardinclination between roll 60 and roll 5 and is straightened to a levelcondition between roll 5 and leaf 106 bearing upwardly against its lowerface. Thus, the strip passes through two stages of bending, firstdownwardly and then upwardly as it passes from straightening roll 61 tobrake 106, 107. Also, the first stage, the downward bend that is givento the strip as it passes over roll 60 is a bend of greater degree thanthe upward bend given to the strip as it passes beneath roll 5. Thus thestrip, as delivered to the punching dies, is absolutely flat andstraight.

An improved mounting for cam shaft 55 is provided, the details of one ofsuch mountings being shown in Fig.

' 13. A trunnion 142, having a knurled outer end, is journalled in acylindrical bore 143 in the upper end of leader pin 51 and its inner endis mounted in a socket in the shaft 55, and is secured by a set screw144. An oil hole is drilled through the upper end of post 51 down tobore 143 and provides for lubricating the bearing wall thereof.

The drive mechanism for this form of the invention is substantially thesame as that shown in Fig. l and the same reference numerals indicatethe various parts there of. It is however, located on the leftward sideof the apparatus as viewed looking in the direction of the feedingmovement of strip K, instead of on the rightward side as in Fig. l, andis therefore symmetrically reversed as indicated in Fig. 13.

Fulcrum roller 119 has end trunnions journalled in bearing blocks 138which are mounted on deck B just inwardly of bushings 51.

Instead of lateral guide rolls 69, the invention utilizes pads 139 whichare mounted on a shaft 146 and secured thereto by set screws 140. Shaft146 is secured in the ends of rails 1, 2 by means of set screws 14%.

I claim:

1. In a roll-feed mechanism for feeding strip stock into a punch presshaving a vertically reciprocating ram carrying an actuator finger: upperand lower feed rolls; a fixed frame in which the lower roll isjournalled; a deck fixedly supported by said frame above the upper roll;a pair of leader pins vertically slidable in said deck; journals carriedby the lower ends of said pins, in which said upper roll is journalled;means spring-loading said journals downwardly; a cam shaft bridgingbetween the upper ends of said pins and journalled thereto; a fulcrumroller carried by said deck below said cam shaft; cam means on saidshaft and bearing against said fulcrum roller; and a release leverattached to said cam shaft and including an actuator arm projectinggenerally radially therefrom and horizontally beneath said actuator armfor engagement thereby; said cam means including a rapidly rising camface terminating in an apex, and a substantially dwell face followingsaid apex, said apex, in approaching an on-center position on saidfulcrum roller, effecting an elevation of said upper roll to a releaseposition within a relatively small portion of the stroke of said lever,and said dwell face allowing a wide range of further downward movementof the release lever with only a moderate further elevation of the upperroll.

2. Roll-feed mechanism as defined in claim 1, wherein said dwell facehas a low-angle rise, so as to automatically return the lever to anelevated starting position in response to said spring-loading means, aspermitted by the upward return of the ram to its starting position.

3. Roll-feed mechanism as defined in claim 2, including a clamp yoke towhich said release lever is secured, said clamp yoke embracing said camshaft and having means for clamping it to the cam shaft in a selectedposition of angular adjustment thereon, whereby to adjust the angularrelation between said lever and said cam means.

4. A feed mechanism as defined in claim 1, wherein said cam has on itsperiphery a flat face, a slowly rising spiral face, and a hump definedbetween said flat face and spiral face, said hump being positioned toengage said fulcrum roller in an early stage of depression of said itriplever and to effect a rapid rise of said cam shaft in said early stage,followed by a slow rise throughout a rela' tively wide angle ofdepression of the lever.

No references cited.

